1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2011 - 2012 Samsung Electronics
4  * EXT4 filesystem implementation in Uboot by
5  * Uma Shankar <uma.shankar@samsung.com>
6  * Manjunatha C Achar <a.manjunatha@samsung.com>
7  *
8  * ext4ls and ext4load : Based on ext2 ls and load support in Uboot.
9  *		       Ext4 read optimization taken from Open-Moko
10  *		       Qi bootloader
11  *
12  * (C) Copyright 2004
13  * esd gmbh <www.esd-electronics.com>
14  * Reinhard Arlt <reinhard.arlt@esd-electronics.com>
15  *
16  * based on code from grub2 fs/ext2.c and fs/fshelp.c by
17  * GRUB  --  GRand Unified Bootloader
18  * Copyright (C) 2003, 2004  Free Software Foundation, Inc.
19  *
20  * ext4write : Based on generic ext4 protocol.
21  */
22 
23 
24 #include <common.h>
25 #include <blk.h>
26 #include <log.h>
27 #include <malloc.h>
28 #include <memalign.h>
29 #include <part.h>
30 #include <linux/stat.h>
31 #include <div64.h>
32 #include "ext4_common.h"
33 
ext4fs_sb_free_inodes_inc(struct ext2_sblock * sb)34 static inline void ext4fs_sb_free_inodes_inc(struct ext2_sblock *sb)
35 {
36 	sb->free_inodes = cpu_to_le32(le32_to_cpu(sb->free_inodes) + 1);
37 }
38 
ext4fs_sb_free_blocks_inc(struct ext2_sblock * sb)39 static inline void ext4fs_sb_free_blocks_inc(struct ext2_sblock *sb)
40 {
41 	sb->free_blocks = cpu_to_le32(le32_to_cpu(sb->free_blocks) + 1);
42 }
43 
ext4fs_bg_free_inodes_inc(struct ext2_block_group * bg,const struct ext_filesystem * fs)44 static inline void ext4fs_bg_free_inodes_inc
45 	(struct ext2_block_group *bg, const struct ext_filesystem *fs)
46 {
47 	uint32_t free_inodes = le16_to_cpu(bg->free_inodes);
48 	if (fs->gdsize == 64)
49 		free_inodes += le16_to_cpu(bg->free_inodes_high) << 16;
50 	free_inodes++;
51 
52 	bg->free_inodes = cpu_to_le16(free_inodes & 0xffff);
53 	if (fs->gdsize == 64)
54 		bg->free_inodes_high = cpu_to_le16(free_inodes >> 16);
55 }
56 
ext4fs_bg_free_blocks_inc(struct ext2_block_group * bg,const struct ext_filesystem * fs)57 static inline void ext4fs_bg_free_blocks_inc
58 	(struct ext2_block_group *bg, const struct ext_filesystem *fs)
59 {
60 	uint32_t free_blocks = le16_to_cpu(bg->free_blocks);
61 	if (fs->gdsize == 64)
62 		free_blocks += le16_to_cpu(bg->free_blocks_high) << 16;
63 	free_blocks++;
64 
65 	bg->free_blocks = cpu_to_le16(free_blocks & 0xffff);
66 	if (fs->gdsize == 64)
67 		bg->free_blocks_high = cpu_to_le16(free_blocks >> 16);
68 }
69 
ext4fs_update(void)70 static void ext4fs_update(void)
71 {
72 	short i;
73 	ext4fs_update_journal();
74 	struct ext_filesystem *fs = get_fs();
75 	struct ext2_block_group *bgd = NULL;
76 
77 	/* update  super block */
78 	put_ext4((uint64_t)(SUPERBLOCK_SIZE),
79 		 (struct ext2_sblock *)fs->sb, (uint32_t)SUPERBLOCK_SIZE);
80 
81 	/* update block bitmaps */
82 	for (i = 0; i < fs->no_blkgrp; i++) {
83 		bgd = ext4fs_get_group_descriptor(fs, i);
84 		bgd->bg_checksum = cpu_to_le16(ext4fs_checksum_update(i));
85 		uint64_t b_bitmap_blk = ext4fs_bg_get_block_id(bgd, fs);
86 		put_ext4(b_bitmap_blk * fs->blksz,
87 			 fs->blk_bmaps[i], fs->blksz);
88 	}
89 
90 	/* update inode bitmaps */
91 	for (i = 0; i < fs->no_blkgrp; i++) {
92 		bgd = ext4fs_get_group_descriptor(fs, i);
93 		uint64_t i_bitmap_blk = ext4fs_bg_get_inode_id(bgd, fs);
94 		put_ext4(i_bitmap_blk * fs->blksz,
95 			 fs->inode_bmaps[i], fs->blksz);
96 	}
97 
98 	/* update the block group descriptor table */
99 	put_ext4((uint64_t)((uint64_t)fs->gdtable_blkno * (uint64_t)fs->blksz),
100 		 (struct ext2_block_group *)fs->gdtable,
101 		 (fs->blksz * fs->no_blk_pergdt));
102 
103 	ext4fs_dump_metadata();
104 
105 	gindex = 0;
106 	gd_index = 0;
107 }
108 
ext4fs_get_bgdtable(void)109 int ext4fs_get_bgdtable(void)
110 {
111 	int status;
112 	struct ext_filesystem *fs = get_fs();
113 	int gdsize_total = ROUND(fs->no_blkgrp * fs->gdsize, fs->blksz);
114 	fs->no_blk_pergdt = gdsize_total / fs->blksz;
115 
116 	/* allocate memory for gdtable */
117 	fs->gdtable = zalloc(gdsize_total);
118 	if (!fs->gdtable)
119 		return -ENOMEM;
120 	/* read the group descriptor table */
121 	status = ext4fs_devread((lbaint_t)fs->gdtable_blkno * fs->sect_perblk,
122 				0, fs->blksz * fs->no_blk_pergdt, fs->gdtable);
123 	if (status == 0)
124 		goto fail;
125 
126 	if (ext4fs_log_gdt(fs->gdtable)) {
127 		printf("Error in ext4fs_log_gdt\n");
128 		return -1;
129 	}
130 
131 	return 0;
132 fail:
133 	free(fs->gdtable);
134 	fs->gdtable = NULL;
135 
136 	return -1;
137 }
138 
delete_single_indirect_block(struct ext2_inode * inode)139 static void delete_single_indirect_block(struct ext2_inode *inode)
140 {
141 	struct ext2_block_group *bgd = NULL;
142 	static int prev_bg_bmap_idx = -1;
143 	uint32_t blknr;
144 	int remainder;
145 	int bg_idx;
146 	int status;
147 	uint32_t blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group);
148 	struct ext_filesystem *fs = get_fs();
149 	char *journal_buffer = zalloc(fs->blksz);
150 	if (!journal_buffer) {
151 		printf("No memory\n");
152 		return;
153 	}
154 
155 	/* deleting the single indirect block associated with inode */
156 	if (inode->b.blocks.indir_block != 0) {
157 		blknr = le32_to_cpu(inode->b.blocks.indir_block);
158 		debug("SIPB releasing %u\n", blknr);
159 		bg_idx = blknr / blk_per_grp;
160 		if (fs->blksz == 1024) {
161 			remainder = blknr % blk_per_grp;
162 			if (!remainder)
163 				bg_idx--;
164 		}
165 		ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx], bg_idx);
166 		/* get  block group descriptor table */
167 		bgd = ext4fs_get_group_descriptor(fs, bg_idx);
168 		ext4fs_bg_free_blocks_inc(bgd, fs);
169 		ext4fs_sb_free_blocks_inc(fs->sb);
170 		/* journal backup */
171 		if (prev_bg_bmap_idx != bg_idx) {
172 			uint64_t b_bitmap_blk = ext4fs_bg_get_block_id(bgd, fs);
173 			status = ext4fs_devread(
174 					   b_bitmap_blk * fs->sect_perblk,
175 					   0, fs->blksz, journal_buffer);
176 			if (status == 0)
177 				goto fail;
178 			if (ext4fs_log_journal(journal_buffer, b_bitmap_blk))
179 				goto fail;
180 			prev_bg_bmap_idx = bg_idx;
181 		}
182 	}
183 fail:
184 	free(journal_buffer);
185 }
186 
delete_double_indirect_block(struct ext2_inode * inode)187 static void delete_double_indirect_block(struct ext2_inode *inode)
188 {
189 	int i;
190 	short status;
191 	static int prev_bg_bmap_idx = -1;
192 	uint32_t blknr;
193 	int remainder;
194 	int bg_idx;
195 	uint32_t blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group);
196 	__le32 *di_buffer = NULL;
197 	void *dib_start_addr = NULL;
198 	struct ext2_block_group *bgd = NULL;
199 	struct ext_filesystem *fs = get_fs();
200 	char *journal_buffer = zalloc(fs->blksz);
201 	if (!journal_buffer) {
202 		printf("No memory\n");
203 		return;
204 	}
205 
206 	if (inode->b.blocks.double_indir_block != 0) {
207 		di_buffer = zalloc(fs->blksz);
208 		if (!di_buffer) {
209 			printf("No memory\n");
210 			return;
211 		}
212 		dib_start_addr = di_buffer;
213 		blknr = le32_to_cpu(inode->b.blocks.double_indir_block);
214 		status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0,
215 					fs->blksz, (char *)di_buffer);
216 		for (i = 0; i < fs->blksz / sizeof(int); i++) {
217 			if (*di_buffer == 0)
218 				break;
219 
220 			debug("DICB releasing %u\n", *di_buffer);
221 			bg_idx = le32_to_cpu(*di_buffer) / blk_per_grp;
222 			if (fs->blksz == 1024) {
223 				remainder = le32_to_cpu(*di_buffer) % blk_per_grp;
224 				if (!remainder)
225 					bg_idx--;
226 			}
227 			/* get  block group descriptor table */
228 			bgd = ext4fs_get_group_descriptor(fs, bg_idx);
229 			ext4fs_reset_block_bmap(le32_to_cpu(*di_buffer),
230 					fs->blk_bmaps[bg_idx], bg_idx);
231 			di_buffer++;
232 			ext4fs_bg_free_blocks_inc(bgd, fs);
233 			ext4fs_sb_free_blocks_inc(fs->sb);
234 			/* journal backup */
235 			if (prev_bg_bmap_idx != bg_idx) {
236 				uint64_t b_bitmap_blk =
237 					ext4fs_bg_get_block_id(bgd, fs);
238 				status = ext4fs_devread(b_bitmap_blk
239 							* fs->sect_perblk, 0,
240 							fs->blksz,
241 							journal_buffer);
242 				if (status == 0)
243 					goto fail;
244 
245 				if (ext4fs_log_journal(journal_buffer,
246 						       b_bitmap_blk))
247 					goto fail;
248 				prev_bg_bmap_idx = bg_idx;
249 			}
250 		}
251 
252 		/* removing the parent double indirect block */
253 		blknr = le32_to_cpu(inode->b.blocks.double_indir_block);
254 		bg_idx = blknr / blk_per_grp;
255 		if (fs->blksz == 1024) {
256 			remainder = blknr % blk_per_grp;
257 			if (!remainder)
258 				bg_idx--;
259 		}
260 		/* get  block group descriptor table */
261 		bgd = ext4fs_get_group_descriptor(fs, bg_idx);
262 		ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx], bg_idx);
263 		ext4fs_bg_free_blocks_inc(bgd, fs);
264 		ext4fs_sb_free_blocks_inc(fs->sb);
265 		/* journal backup */
266 		if (prev_bg_bmap_idx != bg_idx) {
267 			uint64_t b_bitmap_blk = ext4fs_bg_get_block_id(bgd, fs);
268 			status = ext4fs_devread(b_bitmap_blk * fs->sect_perblk,
269 						0, fs->blksz, journal_buffer);
270 			if (status == 0)
271 				goto fail;
272 
273 			if (ext4fs_log_journal(journal_buffer, b_bitmap_blk))
274 				goto fail;
275 			prev_bg_bmap_idx = bg_idx;
276 		}
277 		debug("DIPB releasing %d\n", blknr);
278 	}
279 fail:
280 	free(dib_start_addr);
281 	free(journal_buffer);
282 }
283 
delete_triple_indirect_block(struct ext2_inode * inode)284 static void delete_triple_indirect_block(struct ext2_inode *inode)
285 {
286 	int i, j;
287 	short status;
288 	static int prev_bg_bmap_idx = -1;
289 	uint32_t blknr;
290 	int remainder;
291 	int bg_idx;
292 	uint32_t blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group);
293 	__le32 *tigp_buffer = NULL;
294 	void *tib_start_addr = NULL;
295 	__le32 *tip_buffer = NULL;
296 	void *tipb_start_addr = NULL;
297 	struct ext2_block_group *bgd = NULL;
298 	struct ext_filesystem *fs = get_fs();
299 	char *journal_buffer = zalloc(fs->blksz);
300 	if (!journal_buffer) {
301 		printf("No memory\n");
302 		return;
303 	}
304 
305 	if (inode->b.blocks.triple_indir_block != 0) {
306 		tigp_buffer = zalloc(fs->blksz);
307 		if (!tigp_buffer) {
308 			printf("No memory\n");
309 			return;
310 		}
311 		tib_start_addr = tigp_buffer;
312 		blknr = le32_to_cpu(inode->b.blocks.triple_indir_block);
313 		status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0,
314 					fs->blksz, (char *)tigp_buffer);
315 		for (i = 0; i < fs->blksz / sizeof(int); i++) {
316 			if (*tigp_buffer == 0)
317 				break;
318 			debug("tigp buffer releasing %u\n", *tigp_buffer);
319 
320 			tip_buffer = zalloc(fs->blksz);
321 			if (!tip_buffer)
322 				goto fail;
323 			tipb_start_addr = tip_buffer;
324 			status = ext4fs_devread((lbaint_t)le32_to_cpu(*tigp_buffer) *
325 						fs->sect_perblk, 0, fs->blksz,
326 						(char *)tip_buffer);
327 			for (j = 0; j < fs->blksz / sizeof(int); j++) {
328 				if (le32_to_cpu(*tip_buffer) == 0)
329 					break;
330 				bg_idx = le32_to_cpu(*tip_buffer) / blk_per_grp;
331 				if (fs->blksz == 1024) {
332 					remainder = le32_to_cpu(*tip_buffer) % blk_per_grp;
333 					if (!remainder)
334 						bg_idx--;
335 				}
336 
337 				ext4fs_reset_block_bmap(le32_to_cpu(*tip_buffer),
338 							fs->blk_bmaps[bg_idx],
339 							bg_idx);
340 
341 				tip_buffer++;
342 				/* get  block group descriptor table */
343 				bgd = ext4fs_get_group_descriptor(fs, bg_idx);
344 				ext4fs_bg_free_blocks_inc(bgd, fs);
345 				ext4fs_sb_free_blocks_inc(fs->sb);
346 				/* journal backup */
347 				if (prev_bg_bmap_idx != bg_idx) {
348 					uint64_t b_bitmap_blk =
349 						ext4fs_bg_get_block_id(bgd, fs);
350 					status =
351 					    ext4fs_devread(
352 							b_bitmap_blk *
353 							fs->sect_perblk, 0,
354 							fs->blksz,
355 							journal_buffer);
356 					if (status == 0)
357 						goto fail;
358 
359 					if (ext4fs_log_journal(journal_buffer,
360 							       b_bitmap_blk))
361 						goto fail;
362 					prev_bg_bmap_idx = bg_idx;
363 				}
364 			}
365 			free(tipb_start_addr);
366 			tipb_start_addr = NULL;
367 
368 			/*
369 			 * removing the grand parent blocks
370 			 * which is connected to inode
371 			 */
372 			bg_idx = le32_to_cpu(*tigp_buffer) / blk_per_grp;
373 			if (fs->blksz == 1024) {
374 				remainder = le32_to_cpu(*tigp_buffer) % blk_per_grp;
375 				if (!remainder)
376 					bg_idx--;
377 			}
378 			ext4fs_reset_block_bmap(le32_to_cpu(*tigp_buffer),
379 						fs->blk_bmaps[bg_idx], bg_idx);
380 
381 			tigp_buffer++;
382 			/* get  block group descriptor table */
383 			bgd = ext4fs_get_group_descriptor(fs, bg_idx);
384 			ext4fs_bg_free_blocks_inc(bgd, fs);
385 			ext4fs_sb_free_blocks_inc(fs->sb);
386 			/* journal backup */
387 			if (prev_bg_bmap_idx != bg_idx) {
388 				uint64_t b_bitmap_blk =
389 					ext4fs_bg_get_block_id(bgd, fs);
390 				memset(journal_buffer, '\0', fs->blksz);
391 				status = ext4fs_devread(b_bitmap_blk *
392 							fs->sect_perblk, 0,
393 							fs->blksz,
394 							journal_buffer);
395 				if (status == 0)
396 					goto fail;
397 
398 				if (ext4fs_log_journal(journal_buffer,
399 						       b_bitmap_blk))
400 					goto fail;
401 				prev_bg_bmap_idx = bg_idx;
402 			}
403 		}
404 
405 		/* removing the grand parent triple indirect block */
406 		blknr = le32_to_cpu(inode->b.blocks.triple_indir_block);
407 		bg_idx = blknr / blk_per_grp;
408 		if (fs->blksz == 1024) {
409 			remainder = blknr % blk_per_grp;
410 			if (!remainder)
411 				bg_idx--;
412 		}
413 		ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx], bg_idx);
414 		/* get  block group descriptor table */
415 		bgd = ext4fs_get_group_descriptor(fs, bg_idx);
416 		ext4fs_bg_free_blocks_inc(bgd, fs);
417 		ext4fs_sb_free_blocks_inc(fs->sb);
418 		/* journal backup */
419 		if (prev_bg_bmap_idx != bg_idx) {
420 			uint64_t b_bitmap_blk = ext4fs_bg_get_block_id(bgd, fs);
421 			status = ext4fs_devread(b_bitmap_blk * fs->sect_perblk,
422 						0, fs->blksz, journal_buffer);
423 			if (status == 0)
424 				goto fail;
425 
426 			if (ext4fs_log_journal(journal_buffer, b_bitmap_blk))
427 				goto fail;
428 			prev_bg_bmap_idx = bg_idx;
429 		}
430 		debug("tigp buffer itself releasing %d\n", blknr);
431 	}
432 fail:
433 	free(tib_start_addr);
434 	free(tipb_start_addr);
435 	free(journal_buffer);
436 }
437 
ext4fs_delete_file(int inodeno)438 static int ext4fs_delete_file(int inodeno)
439 {
440 	struct ext2_inode inode;
441 	short status;
442 	int i;
443 	int remainder;
444 	long int blknr;
445 	int bg_idx;
446 	int ibmap_idx;
447 	char *read_buffer = NULL;
448 	char *start_block_address = NULL;
449 	uint32_t no_blocks;
450 
451 	static int prev_bg_bmap_idx = -1;
452 	unsigned int inodes_per_block;
453 	uint32_t blkno;
454 	unsigned int blkoff;
455 	uint32_t blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group);
456 	uint32_t inode_per_grp = le32_to_cpu(ext4fs_root->sblock.inodes_per_group);
457 	struct ext2_inode *inode_buffer = NULL;
458 	struct ext2_block_group *bgd = NULL;
459 	struct ext_filesystem *fs = get_fs();
460 	char *journal_buffer = zalloc(fs->blksz);
461 	if (!journal_buffer)
462 		return -ENOMEM;
463 	status = ext4fs_read_inode(ext4fs_root, inodeno, &inode);
464 	if (status == 0)
465 		goto fail;
466 
467 	/* read the block no allocated to a file */
468 	no_blocks = le32_to_cpu(inode.size) / fs->blksz;
469 	if (le32_to_cpu(inode.size) % fs->blksz)
470 		no_blocks++;
471 
472 	/*
473 	 * special case for symlinks whose target are small enough that
474 	 *it fits in struct ext2_inode.b.symlink: no block had been allocated
475 	 */
476 	if ((le16_to_cpu(inode.mode) & S_IFLNK) &&
477 	    le32_to_cpu(inode.size) <= sizeof(inode.b.symlink)) {
478 		no_blocks = 0;
479 	}
480 
481 	if (le32_to_cpu(inode.flags) & EXT4_EXTENTS_FL) {
482 		/* FIXME delete extent index blocks, i.e. eh_depth >= 1 */
483 		struct ext4_extent_header *eh =
484 			(struct ext4_extent_header *)
485 				inode.b.blocks.dir_blocks;
486 		debug("del: dep=%d entries=%d\n", eh->eh_depth, eh->eh_entries);
487 	} else {
488 		delete_single_indirect_block(&inode);
489 		delete_double_indirect_block(&inode);
490 		delete_triple_indirect_block(&inode);
491 	}
492 
493 	/* release data blocks */
494 	for (i = 0; i < no_blocks; i++) {
495 		blknr = read_allocated_block(&inode, i, NULL);
496 		if (blknr == 0)
497 			continue;
498 		if (blknr < 0)
499 			goto fail;
500 		bg_idx = blknr / blk_per_grp;
501 		if (fs->blksz == 1024) {
502 			remainder = blknr % blk_per_grp;
503 			if (!remainder)
504 				bg_idx--;
505 		}
506 		ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx],
507 					bg_idx);
508 		debug("EXT4 Block releasing %ld: %d\n", blknr, bg_idx);
509 
510 		/* get  block group descriptor table */
511 		bgd = ext4fs_get_group_descriptor(fs, bg_idx);
512 		ext4fs_bg_free_blocks_inc(bgd, fs);
513 		ext4fs_sb_free_blocks_inc(fs->sb);
514 		/* journal backup */
515 		if (prev_bg_bmap_idx != bg_idx) {
516 			uint64_t b_bitmap_blk = ext4fs_bg_get_block_id(bgd, fs);
517 			status = ext4fs_devread(b_bitmap_blk * fs->sect_perblk,
518 						0, fs->blksz,
519 						journal_buffer);
520 			if (status == 0)
521 				goto fail;
522 			if (ext4fs_log_journal(journal_buffer, b_bitmap_blk))
523 				goto fail;
524 			prev_bg_bmap_idx = bg_idx;
525 		}
526 	}
527 
528 	/* release inode */
529 	/* from the inode no to blockno */
530 	inodes_per_block = fs->blksz / fs->inodesz;
531 	ibmap_idx = inodeno / inode_per_grp;
532 
533 	/* get the block no */
534 	inodeno--;
535 	/* get  block group descriptor table */
536 	bgd = ext4fs_get_group_descriptor(fs, ibmap_idx);
537 	blkno = ext4fs_bg_get_inode_table_id(bgd, fs) +
538 		(inodeno % inode_per_grp) / inodes_per_block;
539 
540 	/* get the offset of the inode */
541 	blkoff = ((inodeno) % inodes_per_block) * fs->inodesz;
542 
543 	/* read the block no containing the inode */
544 	read_buffer = zalloc(fs->blksz);
545 	if (!read_buffer)
546 		goto fail;
547 	start_block_address = read_buffer;
548 	status = ext4fs_devread((lbaint_t)blkno * fs->sect_perblk,
549 				0, fs->blksz, read_buffer);
550 	if (status == 0)
551 		goto fail;
552 
553 	if (ext4fs_log_journal(read_buffer, blkno))
554 		goto fail;
555 
556 	read_buffer = read_buffer + blkoff;
557 	inode_buffer = (struct ext2_inode *)read_buffer;
558 	memset(inode_buffer, '\0', fs->inodesz);
559 
560 	/* write the inode to original position in inode table */
561 	if (ext4fs_put_metadata(start_block_address, blkno))
562 		goto fail;
563 
564 	/* update the respective inode bitmaps */
565 	inodeno++;
566 	ext4fs_reset_inode_bmap(inodeno, fs->inode_bmaps[ibmap_idx], ibmap_idx);
567 	ext4fs_bg_free_inodes_inc(bgd, fs);
568 	ext4fs_sb_free_inodes_inc(fs->sb);
569 	/* journal backup */
570 	memset(journal_buffer, '\0', fs->blksz);
571 	status = ext4fs_devread(ext4fs_bg_get_inode_id(bgd, fs) *
572 				fs->sect_perblk, 0, fs->blksz, journal_buffer);
573 	if (status == 0)
574 		goto fail;
575 	if (ext4fs_log_journal(journal_buffer, ext4fs_bg_get_inode_id(bgd, fs)))
576 		goto fail;
577 
578 	ext4fs_update();
579 	ext4fs_deinit();
580 	ext4fs_reinit_global();
581 
582 	if (ext4fs_init() != 0) {
583 		printf("error in File System init\n");
584 		goto fail;
585 	}
586 
587 	free(start_block_address);
588 	free(journal_buffer);
589 
590 	return 0;
591 fail:
592 	free(start_block_address);
593 	free(journal_buffer);
594 
595 	return -1;
596 }
597 
ext4fs_init(void)598 int ext4fs_init(void)
599 {
600 	short status;
601 	int i;
602 	uint32_t real_free_blocks = 0;
603 	struct ext_filesystem *fs = get_fs();
604 
605 	/* populate fs */
606 	fs->blksz = EXT2_BLOCK_SIZE(ext4fs_root);
607 	fs->sect_perblk = fs->blksz >> fs->dev_desc->log2blksz;
608 
609 	/* get the superblock */
610 	fs->sb = zalloc(SUPERBLOCK_SIZE);
611 	if (!fs->sb)
612 		return -ENOMEM;
613 	if (!ext4_read_superblock((char *)fs->sb))
614 		goto fail;
615 
616 	/* init journal */
617 	if (ext4fs_init_journal())
618 		goto fail;
619 
620 	/* get total no of blockgroups */
621 	fs->no_blkgrp = (uint32_t)ext4fs_div_roundup(
622 			le32_to_cpu(ext4fs_root->sblock.total_blocks)
623 			- le32_to_cpu(ext4fs_root->sblock.first_data_block),
624 			le32_to_cpu(ext4fs_root->sblock.blocks_per_group));
625 
626 	/* get the block group descriptor table */
627 	fs->gdtable_blkno = ((EXT2_MIN_BLOCK_SIZE == fs->blksz) + 1);
628 	if (ext4fs_get_bgdtable() == -1) {
629 		printf("Error in getting the block group descriptor table\n");
630 		goto fail;
631 	}
632 
633 	/* load all the available bitmap block of the partition */
634 	fs->blk_bmaps = zalloc(fs->no_blkgrp * sizeof(char *));
635 	if (!fs->blk_bmaps)
636 		goto fail;
637 	for (i = 0; i < fs->no_blkgrp; i++) {
638 		fs->blk_bmaps[i] = zalloc(fs->blksz);
639 		if (!fs->blk_bmaps[i])
640 			goto fail;
641 	}
642 
643 	for (i = 0; i < fs->no_blkgrp; i++) {
644 		struct ext2_block_group *bgd =
645 			ext4fs_get_group_descriptor(fs, i);
646 		status = ext4fs_devread(ext4fs_bg_get_block_id(bgd, fs) *
647 				   fs->sect_perblk, 0,
648 				   fs->blksz, (char *)fs->blk_bmaps[i]);
649 		if (status == 0)
650 			goto fail;
651 	}
652 
653 	/* load all the available inode bitmap of the partition */
654 	fs->inode_bmaps = zalloc(fs->no_blkgrp * sizeof(unsigned char *));
655 	if (!fs->inode_bmaps)
656 		goto fail;
657 	for (i = 0; i < fs->no_blkgrp; i++) {
658 		fs->inode_bmaps[i] = zalloc(fs->blksz);
659 		if (!fs->inode_bmaps[i])
660 			goto fail;
661 	}
662 
663 	for (i = 0; i < fs->no_blkgrp; i++) {
664 		struct ext2_block_group *bgd =
665 			ext4fs_get_group_descriptor(fs, i);
666 		status = ext4fs_devread(ext4fs_bg_get_inode_id(bgd, fs) *
667 					fs->sect_perblk,
668 					0, fs->blksz,
669 					(char *)fs->inode_bmaps[i]);
670 		if (status == 0)
671 			goto fail;
672 	}
673 
674 	/*
675 	 * check filesystem consistency with free blocks of file system
676 	 * some time we observed that superblock freeblocks does not match
677 	 * with the  blockgroups freeblocks when improper
678 	 * reboot of a linux kernel
679 	 */
680 	for (i = 0; i < fs->no_blkgrp; i++) {
681 		struct ext2_block_group *bgd =
682 			ext4fs_get_group_descriptor(fs, i);
683 		real_free_blocks = real_free_blocks +
684 			ext4fs_bg_get_free_blocks(bgd, fs);
685 	}
686 	if (real_free_blocks != ext4fs_sb_get_free_blocks(fs->sb))
687 		ext4fs_sb_set_free_blocks(fs->sb, real_free_blocks);
688 
689 	return 0;
690 fail:
691 	ext4fs_deinit();
692 
693 	return -1;
694 }
695 
ext4fs_deinit(void)696 void ext4fs_deinit(void)
697 {
698 	int i;
699 	struct ext2_inode inode_journal;
700 	struct journal_superblock_t *jsb;
701 	uint32_t blknr;
702 	struct ext_filesystem *fs = get_fs();
703 	uint32_t new_feature_incompat;
704 
705 	/* free journal */
706 	char *temp_buff = zalloc(fs->blksz);
707 	if (temp_buff) {
708 		ext4fs_read_inode(ext4fs_root, EXT2_JOURNAL_INO,
709 				  &inode_journal);
710 		blknr = read_allocated_block(&inode_journal,
711 					EXT2_JOURNAL_SUPERBLOCK, NULL);
712 		ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0, fs->blksz,
713 			       temp_buff);
714 		jsb = (struct journal_superblock_t *)temp_buff;
715 		jsb->s_start = 0;
716 		put_ext4((uint64_t) ((uint64_t)blknr * (uint64_t)fs->blksz),
717 			 (struct journal_superblock_t *)temp_buff, fs->blksz);
718 		free(temp_buff);
719 	}
720 	ext4fs_free_journal();
721 
722 	/* get the superblock */
723 	ext4_read_superblock((char *)fs->sb);
724 	new_feature_incompat = le32_to_cpu(fs->sb->feature_incompat);
725 	new_feature_incompat &= ~EXT3_FEATURE_INCOMPAT_RECOVER;
726 	fs->sb->feature_incompat = cpu_to_le32(new_feature_incompat);
727 	put_ext4((uint64_t)(SUPERBLOCK_SIZE),
728 		 (struct ext2_sblock *)fs->sb, (uint32_t)SUPERBLOCK_SIZE);
729 	free(fs->sb);
730 	fs->sb = NULL;
731 
732 	if (fs->blk_bmaps) {
733 		for (i = 0; i < fs->no_blkgrp; i++) {
734 			free(fs->blk_bmaps[i]);
735 			fs->blk_bmaps[i] = NULL;
736 		}
737 		free(fs->blk_bmaps);
738 		fs->blk_bmaps = NULL;
739 	}
740 
741 	if (fs->inode_bmaps) {
742 		for (i = 0; i < fs->no_blkgrp; i++) {
743 			free(fs->inode_bmaps[i]);
744 			fs->inode_bmaps[i] = NULL;
745 		}
746 		free(fs->inode_bmaps);
747 		fs->inode_bmaps = NULL;
748 	}
749 
750 
751 	free(fs->gdtable);
752 	fs->gdtable = NULL;
753 	/*
754 	 * reinitiliazed the global inode and
755 	 * block bitmap first execution check variables
756 	 */
757 	fs->first_pass_ibmap = 0;
758 	fs->first_pass_bbmap = 0;
759 	fs->curr_inode_no = 0;
760 	fs->curr_blkno = 0;
761 }
762 
763 /*
764  * Write data to filesystem blocks. Uses same optimization for
765  * contigous sectors as ext4fs_read_file
766  */
ext4fs_write_file(struct ext2_inode * file_inode,int pos,unsigned int len,const char * buf)767 static int ext4fs_write_file(struct ext2_inode *file_inode,
768 			     int pos, unsigned int len, const char *buf)
769 {
770 	int i;
771 	int blockcnt;
772 	uint32_t filesize = le32_to_cpu(file_inode->size);
773 	struct ext_filesystem *fs = get_fs();
774 	int log2blksz = fs->dev_desc->log2blksz;
775 	int log2_fs_blocksize = LOG2_BLOCK_SIZE(ext4fs_root) - log2blksz;
776 	int previous_block_number = -1;
777 	int delayed_start = 0;
778 	int delayed_extent = 0;
779 	int delayed_next = 0;
780 	const char *delayed_buf = NULL;
781 
782 	/* Adjust len so it we can't read past the end of the file. */
783 	if (len > filesize)
784 		len = filesize;
785 
786 	blockcnt = ((len + pos) + fs->blksz - 1) / fs->blksz;
787 
788 	for (i = pos / fs->blksz; i < blockcnt; i++) {
789 		long int blknr;
790 		int blockend = fs->blksz;
791 		int skipfirst = 0;
792 		blknr = read_allocated_block(file_inode, i, NULL);
793 		if (blknr <= 0)
794 			return -1;
795 
796 		blknr = blknr << log2_fs_blocksize;
797 
798 		if (blknr) {
799 			if (previous_block_number != -1) {
800 				if (delayed_next == blknr) {
801 					delayed_extent += blockend;
802 					delayed_next += blockend >> log2blksz;
803 				} else {	/* spill */
804 					put_ext4((uint64_t)
805 						 ((uint64_t)delayed_start << log2blksz),
806 						 delayed_buf,
807 						 (uint32_t) delayed_extent);
808 					previous_block_number = blknr;
809 					delayed_start = blknr;
810 					delayed_extent = blockend;
811 					delayed_buf = buf;
812 					delayed_next = blknr +
813 					    (blockend >> log2blksz);
814 				}
815 			} else {
816 				previous_block_number = blknr;
817 				delayed_start = blknr;
818 				delayed_extent = blockend;
819 				delayed_buf = buf;
820 				delayed_next = blknr +
821 				    (blockend >> log2blksz);
822 			}
823 		} else {
824 			if (previous_block_number != -1) {
825 				/* spill */
826 				put_ext4((uint64_t) ((uint64_t)delayed_start <<
827 						     log2blksz),
828 					 delayed_buf,
829 					 (uint32_t) delayed_extent);
830 				previous_block_number = -1;
831 			}
832 		}
833 		buf += fs->blksz - skipfirst;
834 	}
835 	if (previous_block_number != -1) {
836 		/* spill */
837 		put_ext4((uint64_t) ((uint64_t)delayed_start << log2blksz),
838 			 delayed_buf, (uint32_t) delayed_extent);
839 		previous_block_number = -1;
840 	}
841 
842 	return len;
843 }
844 
ext4fs_write(const char * fname,const char * buffer,unsigned long sizebytes,int type)845 int ext4fs_write(const char *fname, const char *buffer,
846 		 unsigned long sizebytes, int type)
847 {
848 	int ret = 0;
849 	struct ext2_inode *file_inode = NULL;
850 	unsigned char *inode_buffer = NULL;
851 	int parent_inodeno;
852 	int inodeno;
853 	time_t timestamp = 0;
854 
855 	uint64_t bytes_reqd_for_file;
856 	unsigned int blks_reqd_for_file;
857 	unsigned int blocks_remaining;
858 	int existing_file_inodeno;
859 	char *temp_ptr = NULL;
860 	long int itable_blkno;
861 	long int parent_itable_blkno;
862 	long int blkoff;
863 	struct ext2_sblock *sblock = &(ext4fs_root->sblock);
864 	unsigned int inodes_per_block;
865 	unsigned int ibmap_idx;
866 	struct ext2_block_group *bgd = NULL;
867 	struct ext_filesystem *fs = get_fs();
868 	ALLOC_CACHE_ALIGN_BUFFER(char, filename, 256);
869 	bool store_link_in_inode = false;
870 	memset(filename, 0x00, 256);
871 
872 	if (type != FILETYPE_REG && type != FILETYPE_SYMLINK)
873 		return -1;
874 
875 	g_parent_inode = zalloc(fs->inodesz);
876 	if (!g_parent_inode)
877 		goto fail;
878 
879 	if (ext4fs_init() != 0) {
880 		printf("error in File System init\n");
881 		return -1;
882 	}
883 
884 	if (le32_to_cpu(fs->sb->feature_ro_compat) & EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) {
885 		printf("Unsupported feature metadata_csum found, not writing.\n");
886 		return -1;
887 	}
888 
889 	inodes_per_block = fs->blksz / fs->inodesz;
890 	parent_inodeno = ext4fs_get_parent_inode_num(fname, filename, F_FILE);
891 	if (parent_inodeno == -1)
892 		goto fail;
893 	if (ext4fs_iget(parent_inodeno, g_parent_inode))
894 		goto fail;
895 	/* do not mess up a directory using hash trees */
896 	if (le32_to_cpu(g_parent_inode->flags) & EXT4_INDEX_FL) {
897 		printf("hash tree directory\n");
898 		goto fail;
899 	}
900 	/* check if the filename is already present in root */
901 	existing_file_inodeno = ext4fs_filename_unlink(filename);
902 	if (existing_file_inodeno != -1) {
903 		ret = ext4fs_delete_file(existing_file_inodeno);
904 		fs->first_pass_bbmap = 0;
905 		fs->curr_blkno = 0;
906 
907 		fs->first_pass_ibmap = 0;
908 		fs->curr_inode_no = 0;
909 		if (ret)
910 			goto fail;
911 	}
912 
913 	/* calculate how many blocks required */
914 	if (type == FILETYPE_SYMLINK &&
915 	    sizebytes <= sizeof(file_inode->b.symlink)) {
916 		store_link_in_inode = true;
917 		bytes_reqd_for_file = 0;
918 	} else {
919 		bytes_reqd_for_file = sizebytes;
920 	}
921 
922 	blks_reqd_for_file = lldiv(bytes_reqd_for_file, fs->blksz);
923 	if (do_div(bytes_reqd_for_file, fs->blksz) != 0) {
924 		blks_reqd_for_file++;
925 		debug("total bytes for a file %u\n", blks_reqd_for_file);
926 	}
927 	blocks_remaining = blks_reqd_for_file;
928 	/* test for available space in partition */
929 	if (le32_to_cpu(fs->sb->free_blocks) < blks_reqd_for_file) {
930 		printf("Not enough space on partition !!!\n");
931 		goto fail;
932 	}
933 
934 	inodeno = ext4fs_update_parent_dentry(filename, type);
935 	if (inodeno == -1)
936 		goto fail;
937 	/* prepare file inode */
938 	inode_buffer = zalloc(fs->inodesz);
939 	if (!inode_buffer)
940 		goto fail;
941 	file_inode = (struct ext2_inode *)inode_buffer;
942 	file_inode->size = cpu_to_le32(sizebytes);
943 	if (type == FILETYPE_SYMLINK) {
944 		file_inode->mode = cpu_to_le16(S_IFLNK | S_IRWXU | S_IRWXG |
945 					       S_IRWXO);
946 		if (store_link_in_inode) {
947 			strncpy(file_inode->b.symlink, buffer, sizebytes);
948 			sizebytes = 0;
949 		}
950 	} else {
951 		file_inode->mode = cpu_to_le16(S_IFREG | S_IRWXU | S_IRGRP |
952 					       S_IROTH | S_IXGRP | S_IXOTH);
953 	}
954 	/* ToDo: Update correct time */
955 	file_inode->mtime = cpu_to_le32(timestamp);
956 	file_inode->atime = cpu_to_le32(timestamp);
957 	file_inode->ctime = cpu_to_le32(timestamp);
958 	file_inode->nlinks = cpu_to_le16(1);
959 
960 	/* Allocate data blocks */
961 	ext4fs_allocate_blocks(file_inode, blocks_remaining,
962 			       &blks_reqd_for_file);
963 	file_inode->blockcnt = cpu_to_le32((blks_reqd_for_file * fs->blksz) >>
964 					   LOG2_SECTOR_SIZE);
965 
966 	temp_ptr = zalloc(fs->blksz);
967 	if (!temp_ptr)
968 		goto fail;
969 	ibmap_idx = inodeno / le32_to_cpu(ext4fs_root->sblock.inodes_per_group);
970 	inodeno--;
971 	bgd = ext4fs_get_group_descriptor(fs, ibmap_idx);
972 	itable_blkno = ext4fs_bg_get_inode_table_id(bgd, fs) +
973 			(inodeno % le32_to_cpu(sblock->inodes_per_group)) /
974 			inodes_per_block;
975 	blkoff = (inodeno % inodes_per_block) * fs->inodesz;
976 	ext4fs_devread((lbaint_t)itable_blkno * fs->sect_perblk, 0, fs->blksz,
977 		       temp_ptr);
978 	if (ext4fs_log_journal(temp_ptr, itable_blkno))
979 		goto fail;
980 
981 	memcpy(temp_ptr + blkoff, inode_buffer, fs->inodesz);
982 	if (ext4fs_put_metadata(temp_ptr, itable_blkno))
983 		goto fail;
984 	/* copy the file content into data blocks */
985 	if (ext4fs_write_file(file_inode, 0, sizebytes, buffer) == -1) {
986 		printf("Error in copying content\n");
987 		/* FIXME: Deallocate data blocks */
988 		goto fail;
989 	}
990 	ibmap_idx = parent_inodeno / le32_to_cpu(ext4fs_root->sblock.inodes_per_group);
991 	parent_inodeno--;
992 	bgd = ext4fs_get_group_descriptor(fs, ibmap_idx);
993 	parent_itable_blkno = ext4fs_bg_get_inode_table_id(bgd, fs) +
994 	    (parent_inodeno %
995 	     le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block;
996 	blkoff = (parent_inodeno % inodes_per_block) * fs->inodesz;
997 	if (parent_itable_blkno != itable_blkno) {
998 		memset(temp_ptr, '\0', fs->blksz);
999 		ext4fs_devread((lbaint_t)parent_itable_blkno * fs->sect_perblk,
1000 			       0, fs->blksz, temp_ptr);
1001 		if (ext4fs_log_journal(temp_ptr, parent_itable_blkno))
1002 			goto fail;
1003 
1004 		memcpy(temp_ptr + blkoff, g_parent_inode, fs->inodesz);
1005 		if (ext4fs_put_metadata(temp_ptr, parent_itable_blkno))
1006 			goto fail;
1007 	} else {
1008 		/*
1009 		 * If parent and child fall in same inode table block
1010 		 * both should be kept in 1 buffer
1011 		 */
1012 		memcpy(temp_ptr + blkoff, g_parent_inode, fs->inodesz);
1013 		gd_index--;
1014 		if (ext4fs_put_metadata(temp_ptr, itable_blkno))
1015 			goto fail;
1016 	}
1017 	ext4fs_update();
1018 	ext4fs_deinit();
1019 
1020 	fs->first_pass_bbmap = 0;
1021 	fs->curr_blkno = 0;
1022 	fs->first_pass_ibmap = 0;
1023 	fs->curr_inode_no = 0;
1024 	free(inode_buffer);
1025 	free(g_parent_inode);
1026 	free(temp_ptr);
1027 	g_parent_inode = NULL;
1028 
1029 	return 0;
1030 fail:
1031 	ext4fs_deinit();
1032 	free(inode_buffer);
1033 	free(g_parent_inode);
1034 	free(temp_ptr);
1035 	g_parent_inode = NULL;
1036 
1037 	return -1;
1038 }
1039 
ext4_write_file(const char * filename,void * buf,loff_t offset,loff_t len,loff_t * actwrite)1040 int ext4_write_file(const char *filename, void *buf, loff_t offset,
1041 		    loff_t len, loff_t *actwrite)
1042 {
1043 	int ret;
1044 
1045 	if (offset != 0) {
1046 		printf("** Cannot support non-zero offset **\n");
1047 		return -1;
1048 	}
1049 
1050 	ret = ext4fs_write(filename, buf, len, FILETYPE_REG);
1051 	if (ret) {
1052 		printf("** Error ext4fs_write() **\n");
1053 		goto fail;
1054 	}
1055 
1056 	*actwrite = len;
1057 
1058 	return 0;
1059 
1060 fail:
1061 	*actwrite = 0;
1062 
1063 	return -1;
1064 }
1065 
ext4fs_create_link(const char * target,const char * fname)1066 int ext4fs_create_link(const char *target, const char *fname)
1067 {
1068 	return ext4fs_write(fname, target, strlen(target), FILETYPE_SYMLINK);
1069 }
1070